Photoelectric device for reading punched cards

ABSTRACT

A photoelectric device for reading punched cards comprising a head having opposed slots for receiving a punched card. A matrix of holes in a back portion of the head is adapted to register with holes in the card. An opening in the front portion of the head exposes the matrix of holes to a light source which is adapted to actuate photocells disposed behind the back portion of the head in registry with the holes in the back portion of the head.

United States Patent 1111 3,586,863

[72] Inventor Herbert Laks [56] References Cited 2] A l N $3 3? Quebec. Canada UNITED STATES PATENTS f 12 1968 304L462 6/1962 Ogle 250/219 1 Patented 1971 3,042,806 7/1962 Lubin... 250/219 2,541,247 2/1951 Herr 250/219 [73] Assignee zillion Electronic Development Company, 3,142,749 7/1964 Larsen-W 250/219 3,360,635 12/1967 Wolfet a1. 235/6l.115 32] Priority zg a g ggg Canada 2,785,388 3/1957 McWhirte et al.. 250/219 [33] 3,051,836 8/1962 Howard 250/219 [31] 983043 Primary Examiner-James W. Lawrence Assistant ExaminerMartin Abramson Attorney-Fetherstonhaugh and Co.

[54] PHOTOELECTRIC DEVICE FOR READING ABSTRACT: A photoelectric device for reading punched PUPKEHED CARPS cards comprising a head having opposed slots for receiving a l Chum 5 Draw Figs punched card. A matrix of holes in a back portion of the head [52] US. Cl 250/219, is adapted to register with holes in the card. An opening in the 235/61.1 1 front portion of the head exposes the matrix of holes to a light [51 1 Int. Cl ..G01n 21/30 source which is adapted to actuate photocells disposed behind 250/219, the back portion of the head in registry with the holes in the 214, 221; 235/61, 115 back portion ofthe head.

[50] Field of PA omTsms/r/M out 7 DIFFA'flE/YIML I AMPUF/ER a 13 /Hm ll/ ms slow/4 l 5 l V I I T [JIM/I76 APPARATUS l9 PATENTEU JUN22 |97| SHEET 1 OF 3 PHOTOIELECTRIC DEVICE FOR READING PUNCHED CARDS BACKGROUND OF THE INVENTION This invention relates to a photoelectric device for reading punched cards having coded patterns of perforations therein disposed in rows and columns. In particular, the present invention relates to a photoelectric device which can provide static readout of a punched card, such as a standard dialer card.

Punched dialer cards are known and comprise opaque cards having coded perforations therein representative, for example, of a telephone number. The dialer card may be inserted into a readout device which reads the telephone number and initiates a dialing operation. Presently known readers are mechanical in nature and utilize mechanical feelers or fingers. Such mechanical devices are relatively large and are subject to malfunction due to mechanical wear of moving parts. Also, they are relatively slow in operation.

SUMMARY OF THE INVENTION The present invention provides a device for statically reading dialer cards or other punched cards which is of very compact construction, dissipates very little power and is not subject to mechanical failure since there are no moving parts except for a card clamping mechanism which is not essential to the invention.

According to the present invention there is provided a photoelectric device for reading punched cards having coded patterns of perforations therein disposed in rows and columns. The device comprises a head having opposed slots therein adapted to receive two opposite edge portions of a punched card. The head has a back portion containing a plurality of rows and columns of holes therein adapted to register with the rows and columns of the punched card inserted in the head and a front portion having an opening therein of sufficient size to expose at least the rows and columns of holes in the back portion to a light source disposed adjacent the opening. The device further comprises a matrix of photocells disposed behind the back portion of the head which has rows and columns of photocells in registry with the rows and columns of holes in the back portion of the head.

The light source is mounted on the front portion of the lead and is preferably a diffuse light source which evenly illuminates the area of the back portion ,of the head which contains the rows and columns of holes. The diffuse light source may comprise a plurality of lamps mounted in a container having reflective inner surfaces except for that surface which faces the front portion of the head, this latter surface comprising a translucent material. Preferably, the lamps are connected in parallel with each other and in series with a resistor whereby, if one or more lamps burn out, the current through the remaining lamps increases and tends to maintain a given total light output from the light source.

The back portion of the head is preferably of sufficient thickness to provide a masking action so that light passing through a hole therein is substantially prevented from striking any photocell other than one in registry therewith.

Each photocell has a pair of electrical leads, one of which is connected to a row wire and the other of which is connected via a diode to a column" wire, the photocell matrix being read by electrically pulsing the row and column wires.

The device preferably includes clamping means adapted to be actuated by insertion slots a card in the head for clamping the card in a stationary position while the photocell matrix is being read.

The head includes a bottom portion defining a bottom for the slots and the opening in the front portion of the head. The clamping means comprises a solenoid secured to the head and having a plunger adapted to pass through the opening in the front of the head and press a card against the back of the head. The solenoid is controlled by current through a trigger photocell which, in turn, is controlled by light from said source passing through a hole in said back portion adjacent said bottom whereby a card fully inserted in the slots blocks light to the trigger photocell so that the solenoid is deenergized thereby allowing its plunger to extend and press the card against the back of the head.

The rows of photocells are deposited on ceramic substrates which, in turn, are secured to an electrically insulating epoxy glass board through holes in which extend the photocell leads. The substrates, together with their photocells, are covered by a thin substantially transparent layer of epoxy. Preferably, a lens is disposed over each photocell and is secured in place by the layer of epoxy.

In order to ensure that light intended for a particular photocell in registry with a hole in a card does not reach a photocell in an adjacent column by scattering within the epoxy layer, it is preferred to apply substantially nonreflective epoxy strips over the substrates between adjacent columns of photocells. The epoxy strips are secured in place by the epoxy layer.

The photocell leads may be connected to a printed circuit board having readout conductors. The readout conductors may be connected to external circuitry by means of a suitable terminal connector.

Readout is accomplished by means ofexternal circuitry which scans the rows and columns of photocells to determine which photocells are illuminated due to the presence of holes in a card which has been placed in the head.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view showing the principal parts of the device according to the present invention,

FIG. 2 is a schematic diagram showing the electrical circuitry of the device,

FIG. 3 is a front view showing the matrix of photocells disposed on ceramic substrates which, in turn, are disposed on an epoxy glass board and also shows the epoxy strips provided between the columns of photocells,

FIG. 4 is a side view partly in cross section of one type of photocell matrix which may be used in the present invention and,

FIG. 5 is a side view, partly in cross section, of a modified form of photocell matrix which may be used in the device according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, there is shown a photoelectric device for reading punched cards, such as card 10, having coded patterns of perforations 12 disposed in rows and columns. FIG. I shows how the perforations are arranged in rows and columns but does not show card 10 as having coded information thereon. It will be readily appreciated that when a card 10 is coded, only certain holes will be present therein.

The device is seen to comprise a head 14 having opposed slots 15 and 16 therein adapted to receive two opposite edge portions 17 and 18 of punched card 10. The head 14 includes a back portion 20 containing a plurality of rows and columns of holes 21 therein adapted to register with the rows and columns of holes 12 in punched card 10 when it is fully inserted in the head. The head 14 also includes a front portion 22 having an opening 23 therein of sufficient size to expose at least the rows and columns of holes 21 in the back portion 20 to a light source 25 disposed adjacent the opening 23. The device according to the invention further comprises a matrix of photocells 30 disposed behind the back portion 20. The photocells 30 are arranged in rows and columns, as can be seen in FIG. 1, and these are in registry with the rows and columns of holes of the back portion 20 of head 14.

The light source 25 is preferably a diffuse light source and is mounted on the front portion 22 of head 14 by suitable means such as screws (not shown) extending through holes 26 in extensions 27 of the front face portion 28 of light source 25 and also through suitable holes 29 in head 14. The diffuse light source 25 preferably comprises a plurality of lamps mounted in a container 31 having reflective inner surfaces except for portion 28 which faces the front portion of the head 1141. This portion 28 comprises a translucent material such as translucent plastic so that the light from the lamps uniformly illuminates the holes 21 in the back portion 20 of head 11 8. The lamps are connected in parallel with each other and in series with a resistor whereby, if one or more lamps burn out, the current through the remaining lamps increases and tends to maintain a given total light output from the light source 25.

The back portion 20 of head 14 is of sufficient thickness to provide a masking action so that light passing through a hole therein is substantially prevented from striking any photocell other than one in registry therewith. Therefore, light passing through a coded perforation in card 1141 and through a hole 21 in registry therewith is permitted to hit that one of the photocells 30 which in registry therewith but, because of the masking action provided by the thickness of the back portion 20, is substantially prevented from striking adjacent photocells.

Preferably, the device is provided with clamping means adapted to be actuated by insertion of a card 110 in the head whereby the card is clamped in a stationary position while the photocell matrix 30 is being read. This clamping means is seen to comprise a solenoid 40 having a plunger 41 and is adapted to be secured to a mounting bracket 42 integral with head 1141 by means of suitable screws (not shown) passing through elongated mounting holes 43 in bracket 42 and through holes in the left side of solenoid 40 which is not visible in FIG. 11. The elongated holes 43 allow for adjusting the position of the solenoid plunger 41 with respect to the back 20 of head 14.

The head has a bottom portion 24 defining a bottom for the slots and I6 and the opening 23 in the front portion of the head 114. The light source 25 illuminates a trigger photocell 83 mounted in epoxy glass board (or other suitable material) 50 by means of hole 45 in the back of head 14. Board 50 also supports the photocells 30. This trigger photocell 83, when illuminated, controls external circuitry, not forming part of this invention, which energizes the solenoid 411) so that plunger 41 is retracted away from the back 211 of head I4. When trigger photocell 83 is not illuminated, the plunger 4111 tends to extend towards the back 20 of head 14. Thus, when a card M1 is fully inserted in slots 15 and 116, it blocks light from source from passing through hole 45 so that the trigger photocell 83 is no longer illuminated. When this happens, the external circuitry mentioned before no longer energizes solenoid 411 so that plunger 41 extends towards the back 241 of head 114 and presses card 10 thereagainst, thereby clamping it against movement. The cessation of illumination of the aforementioned trigger photocell 83 can also be sued to initiate readout of the information contained in card 110, i.e. it initiates scanning" of the rows and columns of photocells 36).

Referring to FIG. 2, it may be seen that each photocell 32 in matrix has a pair of electrical leads, one of which is connected through a diode 33 to a column wire C and the other of which is connected directly to a row wire R. As may be seen in FIGS. 4 and 5, these diodes 33 extend partially through the back 51 of support 50. Referring again to FIG. 11, these diodes also extend through holes 60 in a printed circuit board 61 for connection to suitable printed circuitry on the back of printed circuit board 61. The conductors of the printed circuit extend down the back of printed circuit board at and terminate in tab 62 which is adapted to be inserted in an opening 63 in a terminal connector 64.

The printed circuit board 61 and the epoxy glass board 50 may be secured together and to head 1141 by means of suitable screws (not shown) passing through holes 65 in board 61, holes 66 in board 50, and holes 67 in head 17. Suitable spacers such as 71 may also be provided and between board 50 and board 61, as shown. The head 14 may be provided with a top piece 72 secured thereto by means of suitable screws (not shown) passing through holes 75 in extensions 76 at the top of head 14.

Referring again to FIG. 2, it will readily be appreciated by those skilled in the art that the matrix of photocells may be read by electrically pulsing the column wires C and the row wires R. Thus, one could energize the left-hand column wire C and, while maintaining this energization, pulse each of the row wires R in succession to thereby determine which photocells in the first column have a low resistance due to being illuminated by light passing through holes in the first column of card 110(FIG. I1).

The solenoid 40 is energized by means of line 811 and common line 80. The light source 25 (indicated as a single lamp in FIG. 2) is energized by current over lines 82 and 811 FIG. 2 also shows the trigger photocell 83 having leads 84 and 86 which lead to external circuitry for purposes described hereinbefore. Referring to FIG 11, the leads of the trigger photocell 83 pass through holes 86 in the printed circuit board 611 for connection to suitable printed leads on the back thereof.

Referring to FIG. 3, there is shown the structural details of the photoelectric matrix 30. It is seen to comprise, in this particular embodiment, six rows of photocells 90. The photocells in each row are deposited on ceramic substrates 911, which, in turn, are secured to an epoxy glass board 5111. It may be seen that each photocell has a pair of leads. One lead of each photocell in a row is connected to a common row wire 92 while the other lead is connected through a diode 33 (see FIGS. 2 and 41) to a column wire. The row wires are taken out through the back of board 561 through holes 93 while the other leads extend through the board 50 through holes 941 (see also FIG. 4). Opaque epoxy strips 95 (preferably black) are provided between the columns of photocells 911. An epoxy resin 96 is then cast over the substrates, photocells and strips, as shown in FIG. 4.

FIG. 5 shows an arrangement the same as the arrangement shown in FIGS. 3 and 41 except that small lenses 97 are provided over each photocell 90. This ensures better concentration of light on the photocells. The lenses 9'7 may be fastened to the photocells 911 by means of a bit of epoxy resin, after which the epoxy layer 96 is deposited, thus permanently securing the lenses 97. The lenses may simply comprise small, flat rectangular blocks of transparent plastic material.

It is preferred that the head 14 be made of substantially nonreflective material. The cards MD are, of course, opaque and preferably nonreflective.

While a preferred embodiment according to the invention has been disclosed, various modifications may be effected and the invention is not intended to be limited except as defined by the appended claims.

Iclaim:

11. A photoelectric device for reading punched cards having coded patterns of perforations therein disposed in rows and columns, said device comprising a head having opposed slots therein adapted to receive two opposite edge portions of a punched card, said head having a back portion containing a plurality of rows and columns of holes therein adapted to register with the rows and columns of a punched card inserted in the head and a front portion having an opening therein of sufficient size to expose at least therows and columns of holes in the back portion to a light source disposed adjacent said opening said device further comprising a matrix of photocells disposed behind said back portion and having rows and columns of photocells in registry with the rows and columns of holes in the back portion of the head; said light source comprising a diffuse light source and the back portion of the head being of sufficient thickness to provide a masking action so that light passing through a hole therein is substantially prevented from striking any photocell other than one in registry therewith, said head having a bottom portion defining a bottom for the slots and the opening in the front portion of the head, said device including clamping means adapted to be actuated by insertion of a card in said head for clamping said card in a stationary position while said photocell matrix is being read, said clamping means comprising a solenoid secured to said head and having a plunger adapted to pass back portion adjacent said bottom whereby a card fully inserted in said'slots blocks light to said trigger photocell so that said solenoid is deenergized thereby allowing its plunger to extend and press the card against the back of the head.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 853 Dated June 22 1971 Herbert Laks Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 44, "lead" should read head Column 1, line 65, "slots" should read --of--.

Column 3, line 51, "sued" should read --used--.

Column 4, lines 59-60, after "opening" there should be a semi-colon Signed and sealed this 21st day of January 1975.

(SEAL) Attest:

McCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents Patent No. 3,586,865

Page 2 On the cover sheet, cancel the drawing illustrated and GED BUSES-DC Commas-HUD SUE substitute the following 

1. A photoelectric device for reading punched cards having coded patterns of perforations therein disposed in rows and columns, said device comprising a head having opposed slots therein adapted to receive two opposite edge portions of a punched card, said head having a back portion containing a plurality of rows and columns of holes therein adapted to register with the rows and columns of a punched card inserted in the head and a front portion having an opening therein of sufficient size to expose at least the rows and columns of holes in the back portion to a light source disposed adjacent said opening said device further comprising a matrix of photocells disposed behind said back portion and having rows and columns of photocells in registry with the rows and columns of holes in the back portion of the head; said light source comprising a diffuse light source and the back portion of the head being of sufficient thickness to provide a masking action so that light passing through a hole therein is substantially prevented from striking any photocell other than one in registry therewith, said head having a bottom portion defining a bottom for the slots and the opening in the front portion of the head, said device including clamping means adapted to be actuated by insertion of a card in said head for clamping said card in a stationary position while said photocell matrix is being read, said clamping means comprising a solenoid secured to said head and having a plunger adapted to pass through the opening in the front of the head and press a card against the back of the head, said solenoid being controlled by current through a trigger photocell which, in turn, is controlled by light from said source passing through a hole in said back portion adjacent said bottom whereby a card fully inserted in said slots blocks light to said trigger photocell so that said solenoid is deenergized thereby allowing its plunger to extend and press the card against the back of the head. 